What is the practical answer , I know 4 piece promotes creativity etc ,, however does having another Tom option help your creativity and output ?
I see no practical way that using 4 piece rather than a 5 promotes creativity one way or the other.
The only thing I find it affects is - when I want to play something needing 3 tom pitches, with two toms, I can't and with three toms, I can. Of course, the same could be said of 3 vs. 4 toms - or 1 vs. 2 toms.
Bottomline - IMO it boils down to each player's vocabulary when it comes to the use of toms. Somewhere you hears the toms as high and low most of the time, will gravitate to a 4 piece. Hear things more often in terms of high, medium, and low, then I'd gravitate more to a 5 piece as home base.
Which is the case for me. Actually spent many, many years playing a somewhat compact set with 4 Blaemire toms - 8, 10, 12 and 14 before later settle back into normally playing a 5 piece. Though just recently I've found myself going back and forth between having four toms 10-16 set up - or experimenting with using a (Sput Searight inspired) "Snom" (an 8x14 snare with a hydraulic head tuned to function as a 14" tom, but also as a low FX snare - nestled in with the other toms 10, 12, Snom, 16.
I think the important thing to remember that the drums don't play themselves - just because something is there, doesn't mean we have to hit it. For me, what to set up is dictated by what size pallette I want to have available to me - limited by practical and convenience concerns. But no matter - what I decide to set up, doesn't dictate what I play. Just what I have available to me.